Why are cells small?

(burrito.bio)

36 points | by mailyk 1 hour ago

6 comments

  • chasil 58 minutes ago
    • DaveSchmindel 25 minutes ago
      > Cell sizes are not fixed, however, even within a single species. Cells often swell as they increase their production of proteins and metabolites in preparation for division. This is in line with biology’s only rule: namely, there are exceptions to every rule!

      > Case in point: a giant bacterium called Thiomargarita magnifica can extend about one centimeter in length, so large that it can be seen by the naked eye. It does so by breaking the surface area-to-volume rule, filling between 65–80 percent of its internal volume with an empty vacuole. In other words, it pushes most of its molecules to the cell periphery, thus shortening diffusion distances.

      There is also a captioned image of bubble algae in the post.

    • embedding-shape 20 minutes ago
      Those still seem kind of small? Why not the size of an mature olive tree for example? I'm guessing the article may answer this, haven't gotten that far yet.
  • limbero 30 minutes ago
    Nitpick maybe, but I don't think oocytes are the largest cells, it pretty much has to be some sort of neuron. A sensory neuron for eg. someplace in the foot will be almost as long as the person is tall, and even if the neuron is extremely thin, it's gotta beat the oocyte for volume.
  • kayo_20211030 45 minutes ago
    > A simplistic answer is that evolution has made each cell the size best suited to its function.

    Yeah. That's probably it. Really, it probably is the right answer.

  • gilleain 24 minutes ago
    Surface area to volume ratio?
    • dmd 23 minutes ago
      That's literally the first thing in the article.
  • socalgal2 48 minutes ago
    Cells are small? compared to what? An ostrich egg is a single cell
    • bilsbie 19 minutes ago
      I never bought into the egg thing. There’s clearly a distinct cell in the center that’s going to divide and grow inside the egg. The egg itself isn’t undergoing mitosis.
    • graypegg 40 minutes ago
      I don't know for sure here, but isn't the ostrich IN the egg a multicellular animal? I would assume the first point where the egg contains anything that will become the ostrich, mitosis is happening to make more ostrich cells. I'm assuming there's always cell walls and nucleuses every step of the way here, and the egg and ostrich are never just one big cell.

      I could be off base here though, I'm really channeling grade 9 bio class from decades ago!

      • knappa 19 minutes ago
        Unfertilized bird eggs are single cells, fertilized eggs should be multicellular by the time they are laid.
      • otherme123 25 minutes ago
        The trick is that the egg is a ball with one small cell (the ovum) that happens to have also a huge reservoir of food for the future ostrich. There is a moment when there is only once cell in the egg, just after the fussion of the ovum and the sperm cell.
      • limbero 26 minutes ago
        You're correct, but only for fertilized eggs. Unfertilized eggs are single cells.
    • jackmalpo 21 minutes ago
      skeletal muscle cells can be many cm in length
      • otherme123 5 minutes ago
        A neuron can be more than 1 meter long in humans, more than 20 meter in a whale.
  • WorkerBee28474 58 minutes ago